The foundations of structures, such as bridges and buildings, are principally compressive structures. This is true because the soil and the rocks on which the foundation is placed are fundamentally compressive structures with negligible tensile strength. The action of transferring the loads from a bridge or building structure to the earth may be viewed as a process of transforming the tensile stresses and strains in structural materials into compressive stresses and strains; so these compressive stresses and strains can be transferred to the foundation of the structure and received by the soil and the earth
A variety of inventions and designs have been developed throughout the history of construction to deal with this, lack of tensile strength, characteristic of soil. These inventions have primarily been to introduce various types of discontinuous tensile reinforcing. And while some rock does possess a determinable and predictable tensile strength, this tensile strength is rarely useful while the rock is part of the earth receiving the foundation loadings. Rock can withstand greater compressive loadings than soils and is therefore a better foundation for an above ground structure. It is primarily this greater ability of the rock to receive compressive stresses and compressive forces that makes it a more desirable foundation support.
New building materials products are relatively rare. Most modern building material products came from the last 150 years of industrialization. Modern products include: steel, steel-reinforced concrete, concrete “cinder” blocks, plastics, composites and methods of earth reinforcing, to name a few. Many of these, in their original form, were patented inventions. Prior to these modern products; wood, cut stone, bricks and soils, some glass, cement mortar and base metals were the main menu items from which nearly all construction occurred.
The most recent historical inventions to attempt to improve the ability of the soil to resist tensile loadings have been approaches which combine, with the soil, various types of discontinuous tensile materials in the form of tapes, straps, blankets, cloths, and the like of specific length, width and thickness. These discontinuous tensile materials are usually placed on top of a layer of engineered, compacted soil and then another layer of compacted soil is placed on top of the discontinuous tensile materials and the process is repeated until the desired height is achieved. These discontinuous tensile materials have the effect of integrating the soil into a large, three-dimensional, mass of material that generally combines the compressive properties of the soil with the properties of the discontinuous tensile materials.
The 2005 U.S. consumption of cement is estimated to be one hundred and eight million tons. The redimix concrete market is estimated at three hundred and forty million cubic yards, annually. Based on the cement production and using an average concrete mix design indicates that total concrete market is in the range of four hundred to six hundred million cubic yards.
The cement market in the U.S. is estimated to be distributed as follows:
Utilities1%Residential Buildings31%Water and Waste8%Streets & Highways32%Farm Construction5%Commercial Buildings10%Public Buildings6%Other6%